The present invention relates to a cooling system and method for cooling high heat dissipating components within electronic and computer system enclosures. More particularly, this invention relates to a cooling system for removing heat from high dissipating components located within portable electronic and computer devices having a main body portion and a cover connected in an openable manner to the main body portion.
High heat dissipating components located within small confines of certain consumer electronic devices may create hot spots at certain locations along the external casing of the device. These hot spots may be uncomfortable to the touch, and in some cases may cause injury. Therefore, it is desirable to dissipate heat away from the high heat generating components located within the enclosure of small form factor devices in such a way as to keep the internal components within their specified operating temperature range and to preclude the creation of hot spots along the exterior of the enclosure.
A number of prior techniques have been used to remove heat from heat generating components located within the confines of a computer system enclosure. For example, cooling integrated circuit devices within notebook computers has evolved from the simple attachment of a finned heat sink to the top surface of the device, to the development of finned heat sinks having integral fans. More recent developments have included the use of large, flat heat spreading plates. In such applications, the integrated circuit (generally the CPU) is directly or indirectly attached to a metal plate having a large thermal mass and a large heat transfer surface area. In some instances, the integrated circuit is thermally coupled to the heat spreading plate by a heat pipe. More recently, forced cooling air has been used to cool one side of a heat spreading plate having an integrated circuit attached to the other side. Although these heat transfer methods have proved sufficient in the past, they do not provide the heat removal capacity and/or efficiency needed to cool current and future high-performance microprocessors in portable general-purpose computers and other thin profile electronic devices.
What is needed then is an apparatus and method which solves the aforementioned problems associated with cooling internal electronic circuits located within portable consumer electronic and computer devices. Particularly, what is needed is a highly efficient cooling system that is conformable to the size and power consumption restrictions imposed by small form factor and thin profile electronic devices, such as, for example, notebook computers.
Briefly described, provided herein in one aspect is a cooling system for a portable computer which includes a computer body having a heat generating electronic element therein, and a display section having a screen connected in an openable manner to the computer body. The cooling system includes a cold plate assembly and a heat exchange structure. The cold plate assembly has a surface thermally coupled to the heat generating electronic element, and the heat exchange structure is disposed within the openable display section of the portable computer. The heat exchange structure includes a hollow channel formed therein. A conduit is provided for carrying coolant between the cold plate assembly and the hollow channel of the heat exchange structure; and a circulation pump is also provided for circulating coolant therethrough. Specifically, the circulation pump circulates coolant between the cold plate assembly and the heat exchange structure in a manner so as to cause heat from the heat generating electronic element to be transferred to the coolant, and carried by the coolant to the heat exchange structure for dissipation therefrom. Advantageously, an expansion chamber is integrated within the heat exchange structure disposed within the openable display section of the portable computer. The expansion chamber is in fluid communication with the hollow channel formed in the heat exchange structure and provides space for expansion of the coolant, and a fluid reservoir for the circulation pump from which to draw coolant for circulation through the cold plate assembly.
In another aspect, an electronic apparatus is provided which includes a base housing having a heat-generating component disposed therein, and a lid housing supported on the base housing for movement relative thereto between open and closed positions. A cooling system is also provided for dissipating operating heat generated by the heat-generating component. The cooling system includes a cold plate assembly having a surface thermally coupled to the heat-generating component, and a heat exchange structure disposed within the lid housing. The heat exchange structure includes a hollow channel formed therein. A flexible conduit carries coolant between the cold plate assembly and the hollow channel within the heat exchange structure. A circulation pump is provided for circulating coolant through the conduit between the cold plate assembly and heat exchange structure in a manner causing heat from the heat-generating component to be transferred to the coolant, and carried by the coolant to the heat exchange structure for dissipation therefrom. An expansion chamber is integrated within the heat exchange structure disposed within the lid housing of the electronic apparatus. The expansion chamber, which is in fluid communication with the hollow channel formed in the heat exchange structure, provides space for expansion of the coolant, and provides a reservoir for the circulation pump from which to draw coolant for circulation through the cold plate assembly.
In a further aspect, a method of fabricating a cooling system is provided for a portable computer which includes a computer body having a heat-generating electronic element, and a display section with a screen connected in an openable manner to the computer body. The method includes: thermally coupling a cold plate assembly to the heat-generating electronic element; disposing a heat exchange structure within the openable display section of the portable computer, the heat exchange structure including a hollow channel formed therein; providing a conduit for carrying coolant between the cold plate assembly and the hollow channel within the heat exchange structure; disposing a circulation pump in the computer body for circulating coolant through the conduit between the cold plate assembly and the heat exchange structure in a manner causing heat from the heat-generating electronic element to be transferred to the coolant, and carried by the coolant to the heat exchange structure for dissipation therefrom; and providing an expansion chamber integrated within the heat exchange structure disposed within the openable display section of the portable computer, the expansion chamber being in fluid communication with the hollow channel formed in the heat exchange structure and providing space for expansion of the coolant, as well as providing a reservoir for the circulation pump from which to draw coolant for circulation through the cold plate assembly.
Advantageously, by integrating an expansion chamber within a heat exchange structure disposed in the cover of a portable computer as proposed herein, the limited available space in the base housing of the portable computer is not impacted. Further, by disposing the expansion chamber within the heat exchange structure within the cover, the present invention provides a net positive suction head to a circulation pump disposed within the base housing of the portable computer, thereby preventing the circulation pump from cavitating (resulting in no fluid pumping/movement). With the circulation pump in the base housing and the expansion chamber in the cover, the net positive suction head at the circulation pump inlet is assured. In addition, the expansion chamber provides an ability to handle expansion and contraction of the coolant circulating through the closed loop cooling system in accordance with the principles of the present invention.
Additional features and advantages are realized through the techniques of the present invention. Other embodiments and aspects of the invention are described in detail herein and are considered a part of the claimed invention.